Update Redis config source reference

[emmanuel-ferdman]

Describe changes proposed in this pull request:
Commit 4c3e035 moved the location of RedisConfig.java which leads to broken links in the docs. This PR adjusts sources to changes.

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[alisman]

@emmanuel-ferdman thanks for this PR. Can you put in the comment what problem it addreses?

[dippindots]

Thanks for updating the doc